periodic table Flashcards
alkali metals
found in 1 group, reactive
familes
metals, non-metals, metalloids
john newlands
by physical characteristicis, atomic #
dimitri mendeleev
by atomic mass, left space,invented it
henry mosley
atomic # = # of protons in nucleus, created the 1 we use now
horizontal rows
called periods
verticals columns
called groups, same groups= same properties
lanthanides
naturally found on earth, 7
actinides
all radioactive
metalloids
4
alkaline- earth metals
group 2, less reactive
Transition metals
group 3
non-metals
poor conductors,lack most properties of mental
halogens
group 5, have 7 valence electrons
noble gases
6
francium
most reactive element
staircase group
4 group
electronegativities
increase from left to right,how much electron increase
when move left to right
+ 1 proton and 1 electron
